Brake Fluid Leak problems of the 2011 Ford Ranger

Driving 40 mph down city street, straight, the vehicle in front of me, which I had 4 car length between him and me, stop fast, I put me brakes on and my truck was not responding. I putt both of my feet on the break peddle and it went to the floor and still no respond to the brakes. Well, my truck hit the truck in front and the front of the truck was all messed up, not able to drive it and transmission fluid leaking to the street. After the truck was fix, they tested the brake by pilling each tries off check all the spec, pulled the rotors off and applied the brakes to each wheel one at a time and ran the calibers out to it limits and install the rotors, tires and road tested the brakes check ok at that time but the brake were not at 100% and was still were soft a bit. I ask Ford dealers to install a new master cylinder and each one refused to do that, why, I asked? I received many different answers, but not to why they will not want to install the master cylinder. So, left in a amazement! months later I heard about a recalls on Ford truck with brakes problems, they explain the condition of the problem and my truck fit it to the (t). Now the brakes in my truck is getting softer and not working very well at times. Yesterday, I move the truck, I put the brakes on started the truck and the brakes went to the floor again. Same thing all over again. I am very glad, I used a different car. I was hurt but the next time I might be going faster and well, you get the picture. Help some one please!!!.